Sebastian Vettel pipped Lewis Hamilton to set the fastest time in first practice at the season-ending Abu Dhabi Grand Prix.
The Ferrari driver was 0.12 seconds quicker than the Mercedes of his former title rival, who clinched his fourth championship two races ago in Mexico.
Red Bull’s Max Verstappen was just 0.028secs behind Hamilton, raising hopes of a three-way fight for victory.
Ferrari’s Kimi Raikkonen was fourth ahead of Mercedes’ Valtteri Bottas.
Raikkonen was 0.512secs off team-mate Vettel and Bottas 0.615secs slower than Hamilton.
Force India’s Sergio Perez was sixth quickest ahead of the McLarens of Fernando Alonso and Stoffel Vandoorne.
The first session in Abu Dhabi is not always representative because it takes place in the middle of the day, while qualifying and race are at twilight, when the track temperatures are cooler and the cars, and particularly tyres, behave differently.
Vettel set his time a little later in the session than Hamilton, when the track would have had more grip but a later run by the world champion was a second off the pace after a couple of mistakes.
Felipe Massa’s Williams and Daniel Ricciardo’s Red Bull completed the top 10, while Englishman George Russell, the new GP3 champion and a Mercedes young driver, was 11th on his second practice run-out for Force India, 0.9secs off Perez.
Romain Grosjean had a spin at Turn 19 but managed to set 12th fastest as the Haas team start a weekend in which they, Renault and Toro Rosso are embroiled in a fight for sixth place in the championship on which rests about £10m.
New Zealander Brendon Hartley was slowest for Toro Rosso, with team-mate Pierre Gasly 14th. Hartley has a 10-place grid penalty for using too many engine parts – in this case a ninth example of the MGU-H, the part of the hybrid system that recovers energy from the turbo.